• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.3
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• pp.154-162
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• 2011

Seawater quality was investigated each month at 30 stations near Tongyeong, South Korea, to provide data for the effective use of coastal fisheries and the reduction of economic damage to marine products. Water temperature was lowest in January and highest at the end of August. Neither extremely low water temperature below $4^{\circ}C$ nor fish damage caused by low water temperature was observed. Salinity ranged from 24.04 to 34.39 psu in the surface layer and from 29.92 to 34.39 psu in the bottom layer. The minimum salinity, attributable to rainfall events, was observed in July; salinity increased to high of about 34 psu in November. Low dissolved oxygen (DO), below 4 mg/L, was observed at Wenmun and Buksin Bays during May to October. Concentrations of $NO_2$-N, $NO_3$-N, and $PO_4$-P were low from March to September and high from October to February. Transparency was 6 m on average and was high in Wenmun Bay. Chemical oxygen demand (COD) and chlorophyll a (Chl. a) were high during summer, when the water temperature was high. With cluster analysis based on environment factors related to water quality, the study area could be divided into three main sea areas: Buksin Bay, coastal seawater, and offshore seawater. Buksin Bay was characterized by low salinity, high DO and Chl. a, and high transparency in the surface layer and by low DO and high $NH_4$-N in the bottom layer. Offshore seawater had high salinity and $NO_3$-N and low Chl. a concentration. In summer season that oyster need lots of phytoplankton, $NO_3$-N and Chl. a concentrations at this study area were low compare to Gwangy-ang and Gamak Bays. In winter, a sea squirt swallow much more than other season, the Chl. a concentrations were also low than Gwangyang and Gamak Bays.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.235-244
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• 2004

In this study, we compared the levels of methylotrophic bacterial community diversity in the leaf samples of 19 rice cultivars collected from three regions of Korea. Nineteen pink pigmented isolates showing characteristic growth on methanol were obtained. Physiological and biochemical characters of each isolate were examined according to methods described in Bergey's Manual of Systematic Bacteriology. When phylotypes were defined by performing numerical analysis of 37 characteristics, four distinct clusters were formed. The two reference strains, Methylobacterium extorquens AM1 and Methylobacterium fujisawaense KACC10744 were found to group under cluster IV and cluster III respectively. Cluster I diverged on the basis of nitrate reduction and four isolates showed tolerance upto 0.5 M NaCl concentrations. Two strains in cluster I and III were found to possess methane utilizing properties. Most of the isolates in all the four clusters utilized monosaccharides, disaccharide and polyols as carbon source. When the isolates were subjected for indole-3-acetic acid (IAA) analysis in the presence of L-tryptophan, only 8 isolates exhibited IAA production. In addition, the nitrogen source in the medium was found to influence the IAA production. Addition of $(NH_4)_2SO_4$ in the medium led to a 2 to 30 fold increase in the indole synthesis. However, $KNO_3$, $NH_4NO_3$ and $NH_4Cl$ substitution did not significantly stimulate the synthesis of IAA in the growth medium. Result of gnotobiotic root elongation assay significantly increased roots and shoots lengths, and number of lateral roots, which is mediated by IAA production in the culture medium. The rice seedlings primary roots from seeds treated with methylotrophic isolates were on average 27 to 56% longer than the roots from seeds treated with the uninoculated seeds. In addition, application of different high concentrations of authentic IAA ($400g\;mL^{-1}$) to roots of rice seedlings inhibited root growth. However, the IAA concentration from 10 to $200g\;mL^{-1}$, IAA promoted root growth of rice seedlings. These results suggest that bacterial IAA plays a major role in the development of the host plant root system.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.5
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• pp.14-28
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• 2017

Mt. Seunghak's Miscanthus sinensis community is not only a landscape resource in terms of cultural services within the Ecosystem Services but also a site that is visited by many mountaineers in autumn. As the current Miscanthus sinensis community has been experiencing a rapid decline due to Korean forest succession characteristics, ongoing artificial management is thought to be needed for landscape resource use. The purpose of this study was to determine growth environment characteristics and the cause of the rapid decline of the Miscanthus sinensis community in Mt. Seunghak, which is located inside a large city with a large scale and outstanding accessibility. As the Miscanthus sinensis community is the representative early vegetation that appears temporarily in dry, barren soil, the Miscanthus sinensis community in Korean forest succession tends to be unsustainable. As the current soil on Mt. Seunghak is inappropriately fertile for the Miscanthus sinensis community, other wetland woody plant communities are anticipated to succeed it. If Miscanthus sinensis community maintenance is needed for Miscanthus sinensis landscape scenery, various alternatives apart from overall Miscanthus sinensis community maintenance should be determined for cost-effective management. For example, while many byways toward the inside of the Miscanthus sinensis community have affected the Miscanthus sinensis community growth environment, the installation of wooden fences and ropes has been a control in approach. As a result of this positive effect, many byways toward the inside of Miscanthus sinensis community have been restored naturally. Through viewable range analysis, as good scenery sites on the observatory have a good viewable range on the main trail as well, if these scenery sites are intensively managed, effective Miscanthus sinensis ccommunity management will be done despite maintenance budget cutbacks. This study is expected to be used as a basic material regarding the alternatives for a sustained Miscanthus sinensis community and the possibility of cultivating other growth in poor soils of fallow fields and unused land.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.205-215
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• 2009

In order to understand on the seasonal dynamics of phytoplankton in the mouth parts of Gamak Bay, Korea, we investigated from one station during June 2005 to June 2006. Samples were collected every week during the high water temperature (${\geq}20^{\circ}C$), and every two weeks during the low water temperature (${\leq}20^{\circ}C$). The phytoplankton community were composed of 76 genera, 208 species in the surface layer, and 72 genera, 186 species in the bottom layer (total: 77 genera, 214 species). The number of occurring species fluctuated greatly throughout the year from 27 species (March 15, 2006) to 121 species (Aug. 16, 2005). High number of species showed between June and September (>70 species), whereas the low number of species showed during the period of the low water temperature below $20^{\circ}C$ (ca. 40 species). The predominant species were diatom Skeletonema costatum during whole year, and two naked dinoflagellates, Cochlodinium polykrikoides and Polykrikos kofoidii during high temperature seasons. However, centric diatoms, Chaetoceros curvisetus, Chaetoceros debilis and Eucampia zodiacus were dominant species during low temperature seasons. Standing crops of dinoflagellate showed great fluctuations, which were ranged from $3.0{\times}10^5\;cells\;L^{-1}$ (April 17, 2006) to $7.3{\times}10^5\;cells\;L^{-1}$ (Aug. 2, 2005) in the surface layer and from $1.5{\times}10^3\;cells\;L^{-1}$ (Nov. 9, 2005) to $3.9{\times}10^5\;cells\;L^{-1}$ (Aug. 16, 2005) in the bottom layer, and showed high during high temperature seasons such as the number of species. The fluctuations were greater in the surface layer than in the bottom layer. Moreover, the variation of Cochlodinium polykrikoides, is affected by Polykrikos kofoidii grazing.

• Land and Housing Review
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• v.4 no.1
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• pp.77-87
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• 2013

About 1,800 villages have released from Greenbelt since Greenbelt-reform-policy for readjustment of the area was promoted after 1997. Even though the government intended to attract planned development & improvement of these lifted villages through District Unit Plan and designating the lifted area as low-rise and low-density zoning considering the characteristics of the Greenbelt region, there are still many problems to be solved: a lack of funds, insufficient capability for self-improvement and unexecuted SOCs in long-term etc. It seems that these problems are caused by focusing on the lifting areas itself instead of researching deeply the condition and characteristics of the villages and searching proper direction/plans of improvement before lifting Greenbelt In addition, the existing plan of village improvement and management was not considering physical and spacial characteristics of the areas, social and economic situation of residents and relationship between the villages and surrounding cities, though these conditions are different among each villages, and the related regulations are applied uniformly across all the villages and those have been causing many civil appeals and environmental problems. In these respects, this study aims to consider the problems of the lifted villages using the existing researches on them and to make typology by characteristics-data of the villages and to establish improvement strategies of each types. In this study, the villages were classified into 5 types as a result of cluster analysis on 424 villages among all 1,800 through variables of locational potentiality : location, accessibility, size and form of village, condition of regulations etc. According to function of the villages, they were divided into 4 types: urban-type, rural-type, industrial-type and neighborhood-centered-type. This study also drew 4 improvement-strategy-types by combination of locational potentiality and village-function : type of improving life-environment, type of improving production-infra, type of inducing-planned-improvement and type of constructing center-of living-circle. Finally, this study suggested the directions of the each 4 types to desirable improvement and management which could be used to make and complement plans for village improvement.

• Korean Journal of Environment and Ecology
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• v.27 no.1
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• pp.85-98
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• 2013

In order to propose effective conservation management plan, this study verified ecological characteristics, humanities and Social characteristics. The research site is private property which is owned belonging to the Kim's of Gimhae that have long history. The study site is more than a thousand years old and was created for protecting from typhoon. There held the religious ritual what is called Dongsinje until 1960s. There have been protected and managed by the villagers. As the results of analysis, the area of windbreak are $12,392.69m^2$. The windbreak is dominated old years deciduous broad-leaved tree such as Zelkova serrata, Celtis sinensis, Aphananthe aspera. Around there were farmlands(52.1%), urbanized area(26.3%), forest area(16.6%). The vegetation communities of windbreak were classified by considering the dominant species and current status of forest. The forest types are following as; A. aspera community(I) which is using less pressure, Platycarya strobilacea-Carpinus coreana-Z. serrata community(II). Z. serrata community(III) which is using high pressure, Z. serrata-A. aspera community(IV), Z. serrata community(V) which is damaged under canopy trees. The windbreak was in good condition whereas, there were concerns the some wrong status was being undermined such as the wrong forest restoration projects in the past, the trails that is penetrating inside the forest, building up education facilities. Therefore, in order to restore the value of windbreak what is so called Suwol forest, we should improve the problems of forest ecosystem such as wrong management, forest fragmentation by facilities and decline in forest by lack of growing the next generation trees. In addition, we should remove excessive resting facilities and lead to passive use of forest. to improve the way of wrong management, moreover, we should close off he trails that is penetrating inside the forest for improving fragmentation. We should restore vegetation restoration and fostering the next generation trees for forest ecosystem. In order to restore unique of histo-cultural and ecological forest landscape, the next generation trees should be grown up that is the dominant species in Suwol forest. Moreover, as a results of comparing the between good vegetation communities and damaged vegetation communities, it is necessary to complementary planting for demeged vegetation communities, therefore there needs to 10.8 under canopy trees, 79.7 shrubs.

• Journal of agricultural medicine and community health
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• v.29 no.1
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• pp.43-63
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• 2004

Objectives: The purpose of this study was to classify the patterns of health behaviors of some rural residents in Korea by sub-grouping them into populations with similar patterns of diet quality, physical activity, alcohol consumption and cigarette smoking, and then to investigate the relationship between these health behavior patterns and health status or health management of them. Methods: The study subjects were 722 rural residents above 20 years old on a typical rural district in Korea, and the data used in this study was from the survey data for health planning of a health center. Study questionnaire for this survey was developed from modifying the questionnaire for 'National Nutrition and Health Study' conducted in 1998. To classify health behavior patterns, cluster analysis was conducted. And to test the association of health behavior patterns with health status or health management, multiple logistic regression analysis were conducted. Results: The results and their implications of this study were as follows: 1. We identified six health behavior typologies : 67.8% of the sample had a good diet quality but showed sedentary activity level(good diet lifestyle) and 10.9% had heavy smoking behavior(smoking lifestyle). Individuals included in fitness lifestyle cluster(6.2%) had high physical activity level and those in drinking life style(2.6%) had had mainly large amount of alcohol. Zero point six percent of sample were included in hedonic lifestyle cluster, who showed poor health behaviors in all. Those included in passive lifestyle(11.9%) had no active health promoting activities but tended to avoid risk taking health behavior such as cigarette smoking and alcohol drinking. 2. As a result of logistic regression analysis, to compare with the individuals in good diet lifestyle, the prevalence of chronic diseases of those in fitness lifestyle showed higher and that of those in smoking lifestyle, drinking lifestyle, hedonic lifestyle, passive lifestyle showed lower than them, retrospectively. 3. Adjusting with general characteristics and health status, to compare with the individuals in good diet lifestyle, the proportion of those who had good health management practices in fitness lifestyle was higher, and the proportion of those who had health check in past 2 years was lower than them, retrospectively. Conclusions: There were some differences in health behavior patterns between rural population and national population, which influenced significantly on health status and health management practice of them. We suggested that the health promotion program for them be developed with considering these points.

• Korean Journal of Environment and Ecology
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• v.18 no.1
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• pp.75-91
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• 2004

Biodiversity and seasonal community composition of benthic macroinvertebrates were studied from Upo wetlands in Gyeongsangnam-do, Korea, comprising Upo (4 sites), Mokpo (2 sites), Sajipo (1 site), Jjokjibeol (1 site), Yeobeol (1 site), and Topyeongcheon (2 sites) areas from October 2002 to August 2003. As a result, it was known that Upo wetlands retained relatively well-preserved littoral zones which may provide good habitats for benthic macroinvertebrates; however, frequent disturbances of littoral zones caused by flood were the major factor affecting on the survival and distribution of benthic macroinvertebrates in the areas. During the study period, a total of 135 species of benthic macroinvertebrates in 10 genera, 59 families, 16 orders, 7 classes, and 3 phyla were collected those of which are the highest degree of diversity of the taxa ever known in Korean wetlands: aquatic insects 103 spp. (Diptera 27 spp., Odonata 24 spp., Coleoptera 19 spp., Hemiptera 16 spp., Ephemeroptera 9 spp., Trichoptera 7 spp., and Collembola 1 sp.), Crustacea 2 spp., Mollusca 19 spp. (Gastropoda 12 spp. and Bivalvia 7 spp.), and Annelids 11 spp. (Oligocaeta 1 sp. and Hirudinea 10 spp.). Sajipo (St.G) and Jjokjibeol (St.H) areas yielded relatively larger numbers of species, 54 spp. and 53 spp., respectively, while more than 40 species occurred at most other sites. Based on quantitative sampling (0.5m${\times}$2m), aquatic insects (88.0％), particularly chironomids in Diptera (61.0％), occupied major proportion of the total individuals of benthic macroinvertebrates, while Mollusca (5.3％), Annelida (3.5％), and Crustacea (3.2％) occupied minor proportions. In standing water areas, diverse groups of benthic macroinvertebrates such as chironomids, demselflies, aquatic bugs, aquatic beetles, crustaceans, and gastropods were dominant in terms of individual number; in the running water areas, on the other hand, chironomids and baetid mayflies were dominant. However, gastropods, i.e. viviparids, were the dominant group of benthic macroinvertebrates in most study areas in terms of biomass. Dominance indices were 0.22-0.51 (mean$\pm$sd 0.42$\pm$0.09) in autumn, 0.31-0.96 (0.02$\pm$0.23) in winter, and 0.30-0.89 (0.57$\pm$0.18) in summer; diversity indices were 3.50-4.26 (3.80$\pm$0.24) in autumn,1.55-4.50 (3.10$\pm$1.01) in winter, and 1.35-3.77 (2.55$\pm$0.09) in summer. Highly movable or true aquatic benthic macroinvertebyates such as aquatic bugs, aquatic beetles, and gastropods recovered earlier after flood. In the study sites of Upo wetlands, Upo and Sajipo areas showed relatively higher values of average diversity index which may indicate a good habitat condition for benthic macroinvertebrates.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.3
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• pp.199-213
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• 2020

Grain size and shape are the two important components contributing to rice yield and quality. To analyze traits related to grain-shape, a total of 272 varieties derived from japonica, japonica black and Tongil-type rice accession in Korea were evaluated in this study. The traits, grain length (GL), grain width (GW), grain thickness (GT), length to width ratio (RLW), and 1000-grain weight (TGW) were measured and replicated 10 times. Genes (GW2, GS3, qGL3, qSW5, GS5, TGW6, GW7, and GW8) related to grain-shape were validated in the accessions using specific DNA marker sets. K-mean clustering of the accession based on phenotypic data revealed three groups: group 1 was classified by GW and GT and included most of japonica type, group 2 was classified by RLW and GL reached a medium size and possessed a half spindle-shaped type, and group 3 was classified by TGW, reached a long size and possessed a semi-round shape. In validation tests using the marker sets, both gw2 and tgw6 were validated in less than 1% of the tested accessions and two allelic types, qgl3 and gw8, were only verified in Tongil-type accessions. For GW8 and GW2, any different amplicons were not amplified in any japonica or Tongil-type accessions, respectively. In order to suggest the representative grain-shape gene combinations for each ecotype, the allelic combinations were evaluated by PCR analysis. Cj1 and 2 in japonica (Cj1-7), Cj_b1 and 2 in japonica-black (Cj_b1-3), and CT3 in Tongil-type (CT1-13) turned out to be the dominant combination in each ecotype, respectively. In addition, the results revealed that introgression of four genes (gw2, gs3, qSW5, and GS5) would expand the diversity of grain shape in Korean japonica varieties. The gene combinations information could be utilized practically to understand or enhance grain shape in japonica rice breeding program.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.2
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• pp.319-344
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• 2015

A seasonal characteristic of marine environment and fish assemblages in the coastal waters of Jeju Island were determined using samples collected by a trammel net in from 2012 to 2013. Annual mean temperature and salinity were $18.8^{\circ}C$, 33.7psu (2012) and $18.8^{\circ}C$, 33.8psu (2013) which shows stable water mass. nutrient concentrations represent that dissolved inorganic nitrogen (DIN) ranged from 0.030 to 0.217mg/L, dissolved inorganic phosphorus (DIP) from 0.002 to 0.010mg/L, and silicate ($SiO_2$) from 0.096 to 0.292mg/L. Chlorophyll a concentrations of phytoplankton ranged from 0.905 to $1.125{\mu}g/L$ were appeared the highest in summer and the lowest in winter. Suspended Solid(SS) concentrations ranged from 1.200 to 2.100mg/L (mean, 1.634mg/L) were appeared the highest in autumn and the lowest in spring. During the survey period, a total of 83 species (48 families and 12 orders) of fishes were identified, Perciformes and Scorpaeniformes accounted for 63.9% of the total number. The number of species was higher in summer than in winter, showing a peak in summer at 57 species and a low in winter at 47 species. The number of individuals and the biomass peaked in summer at 694 individuals and 151.9kg, and were the lowest in autumn at 466 individuals and 106.5kg. The diversity index, evenness index and richness index were appeared 2.92~3.14, 0.75~0.83 and 7.06~8.56 at each stations. the dominance index were appeared highest in spring and summer, were appeared the lowest in winter and autumn. The Filefish (Stephanolepis cirrhifer), Bluestriped angelfish (Chaetodontoplus septentrionalis), Marbled rockfish (Sebastiscus marmoratus), Rabbit fish (Siganus fuscescens), Blackfin sweeper (Pempheris japonica) were dominant species, which occurred abundantly during the entire survey period. The subtropical fishes were identified total of 41 species (49.4%) and the number of species was higher in summer at 29 (50.9%) species and a low in winter at 20 (42.6%) species. The dominant species of subtropical fishes were appeared Bluestriped angelfish, Blackfin sweeper, Rabbit fish, Scarbreast tuskfish (Choerodon azurio), Ballonfish (Diodon holocanthus), Flagfish (Goniistius zonatus), Blue-spotted boxfish (Ostracion immaculatus) in study sites. The subtropical fishes of species, individual and biomass showed significant correlation with environmental factors (Chlorophyll a, DIN, DIP, $SiO_2$) in almost all sampling sites.